Collaborative Research: Dynamics of Mauna Loa's and Kilauea's magmatic systems from physics-based modeling

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Dynamic linkage between volcanoes has implications for long- and short-term eruption forecasting. Although such linkage has been suggested to exist for some volcanic systems it remains controversial, as does the underlying mechanism. Recently, the possibility of dynamical coupling of Kilauea and Mauna Loa has been proposed as a consequence of pressure diffusion within an asthenospheric melt zone that underlies both volcanoes, and from which each volcano is supplied with melt, albeit from different parts of it. To test this hypothesis, we propose to construct a numerical model of combined subsurface magma flow and accumulation, magma degassing and volcano deformation. The magma flow model will be based on two-phase flow theory, with magma degassing incorporated from existing solubility and diffusivity formulations for magmatic volatiles. Volcano deformation will be modeled by coupling the flow model with well-established kinematic deformation models through mass conservation. Similarly, changes in magma composition will be estimated from mass balance considerations. Observations of surface deformation, gas emissions and changes in magma composition will constrain the time-dependent magma supply to each volcano. Model results will be used to test for correlative activity and assess potential mechanisms for dynamical coupling. In addition to testing this coupling hypothesis, the model can be used to interrogate the interplay between magma supply, storage and eruptive activity at each volcano, in particular at Kilauea, where the spatial and temporal frequencies of observations are high. In order to demonstrate the capabilities of this proposed modeling approach we will perform an exploration of the unknown parameters the model will include and all the available constraints. We will establish databases of the available geodetic, seismic, geochemical and gas observations, evaluate their completeness and reliability, and ascertain the model uncertainties and trade-offs, assessing the uniqueness of solutions and the statistics of the inverse problem.2013 marked the centennial of the Hawaiian Volcano Observatory located on Kilauea, Earth's most active, and near Mauna Loa, Earth's largest volcano. Both volcanoes are also two of the best and longest monitored volcanoes and have been instrumental to our understanding of the structure and dynamics of the Earth's mantle, the evolution of volcanic island chains, as well as basaltic volcanism in general. They are thought to be the archetypical manifestations of hot-spot volcanism, caused by a buoyantly upwelling mantle plume that undergoes partial melting at a few hundred kilometers depth beneath Hawaii. Upward percolation and accumulation of this melt results in spatially focused flow through the Hawaiian lithosphere, into magma chambers that are located at a few kilometers depth beneath each volcano, and from which volcanic eruptions are fed. Both volcanoes exhibit complex patterns of activity, including movement along large fault planes that underlie portions of each edifice, with the potential for large earthquakes, tsunamis and triggering of new eruptions. It has been suggested that magma accumulation at depth may itself facilitate movement on these faults. Whether these processes and feedbacks are confined to a single volcano or whether they may also affect the neighboring volcano remains uncertain. Future eruptions, especially from Mauna Loa, have significant potential to directly impact the main populations centers on the island of Hawaii, and an improved understanding of the processes at work within the volcanoes, and any dynamic link between then will benefit public safety through increased understanding of volcanoes and volcanic hazards. This project, which represents a collaborative effort between the University of Hawaii, Rice University and the US Geological Survey, is aimed at integrating a range of different types of observation and will, therefore, impact a number of different fields, including geodesy, seismology and geochemistry. Moreover, to maximize the public and educational impact, we will partner with New Media Arts classes from Kapiolani Community College.